Tom Aley spent a fortune and more than 30 years of his life defending a creature no bigger than a grain of sand. Beautiful madness or crazy vision?

When people want a hydrogeologist who can fathom the groundwater, they call Aley. And now that kudos are rolling in, he's bored by it, bored by the prospect of jetting around the world, pronouncing expert truths.

He'd rather pry a grain-sized bubble from the mud.

A John Deere bulldozer stands ready near a huge mulch pile, waiting for the two staffers the Aleys hired to help rehabilitate the land. Add those expenses to the mortgages, and Project Cavesnail is costing them about $350 a day, seven days a week.

Jennifer Silverberg

Jennifer Silverberg

Tom Aley and his wife, Cathy, deep in the underground home of the cavesnail

Aley tosses the number as he bounces the SUV across another field. The ground is laid bare, overgrazed and eroded, littered with cow skeletons. Folks call this section Death Valley because the cows came here to die. The land itself is dead, scarred by erosion gullies that look like incisions with chunks of flesh missing. Originally oak-and-hickory woodland, it was bulldozed fence to fence for pasture. Now sediment pours off its surface, clouding the groundwater, plugging up openings in the gravel matrix, clogging the interstices of the cave.

And fucking with the cavesnail.

"You get covered in sediment, your food's covered in sediment, your gills are clogged with sediment," says Aley, angry as an outraged social worker defending the underclass.

Erosion gullies on his new land run 5 feet deep. He scuffs gently at a swirl of soft green vegetation, nudges away a cow skull.

"This owner had about 500 cows on 1,350 acres," he says. "When he cleared this pasture, he pushed all the trees into the valleys, where the stream has to cut around them and make more channels. We pull out the stumps and push the soil back up where it belongs, make U-shaped swales and mulch them."

The first swales have already grassed over, and the newest is about to be seeded.

"I used to get paid for doing this," he says wryly, remembering erosion-control studies he did for the Forest Service. "Now I'm spending money for the privilege."

They have already filled in 2,600 feet of ditch and by May could have as much as two miles of scarring healed. The neighbors are watching in amazement: Nobody else around here does this kind of thing with the land. Many have managed it well enough that there's no need -- but even if there were, they couldn't afford the rehab.

"If a typical person bought land, even land this bad, they'd have to make some money with it," says Aley. "What this land needs is to rest for a year."

He breaks off to wave at a passing truck -- "Gotta say hello to the neighbors" -- then tries to describe how desperate a dairy farmer can get, throwing more and more cows on his land to stave off bankruptcy.

He climbs back into the Montero and drives to the next field. This one he calls Afghanistan. He parks at the edge and steps over the fence, its bottom third buried in gravel that washed downhill.

He walks uphill alongside a deep gully, then stops to peer into a sudden plunge pool. Frayed brown roots drip down the top edge, far above the surface of water that has scoured the bottom so deep that it looks dark green.

"That," says Aley, "is as bad as it gets."

Aley once dreamed of his underground laboratory as a hotbed of international research. Then politicians lost their constituents' trust and spooked -- and all those unsexy grants for basic research froze cold.

Today, Aley snorts phlegm at the notion of anyone agreeing to fund studies of a snail smaller than the last vestige of political imagination.

Resigned to a lonely cause, he and Cathy compile as much information as they can, talk up their snail at scientific cocktail parties and continue their monitoring.

Last year, they didn't find a single cavesnail at any of the established stations.

They panicked. Was it over, as simply as that?

They widened their search and found 40 cavesnails huddling upstream from an old, perhaps muddied haunt.

Area biologists agree with the Aleys' theory of sediment. They assume the cavesnail breathes by fluffing air over its gills, a process easily clogged by silt. They believe it reproduces by laying eggs, but exactly how and when those eggs are laid -- and whether the silt suffocates the babies as they hatch -- nobody knows.

What they do know is that last fall, in the well-upholstered office of the Secretary of the Interior, the cavesnail got lucky.

The U.S. Department of the Interior had missed many a mandatory deadline in its underfunded, fumbling attempts to protect endangered species. Three conservation groups -- the Center for Biological Diversity, the Southern Appalachian Biodiversity Project and the California Native Plant Society -- offered to stop brandishing lawsuits if the department would spend all that lawyering money on protection. Then they all sat down together and listed the 29 species in the direst straits, granting them emergency protection for 240 days.

Alongside the pygmy rabbit and the showy stickseed, just up from the Mississippi gopher frog, was Missouri's Tumbling Creek cavesnail.

For Aley, the settlement was pure bonus: The U.S. Fish & Wildlife Service had known of the cavesnail's existence for years, and he had kept them posted on its decline, but he'd never pushed for special consideration. In the Ozarks, the topic of federal protection is stickier than snail slime.